Heating furnace



Sept. 22, 1925.

A. J. MASKREY HEATING FURNACE Filed Feb. l225, 1922 Patented Sept. 22,1925.

ARTHUR J. MASKREY; or' CANToNyoHIo.

HEATING rUnNAcE.

Application led February l23, 192,2. v Serial No. 538,731.y Y

. To all whom t may concern.'

Be it known that I, ARTHUR J. MAsKRnY,

ya citizen of the United States, residing at Canton, in the county ofStark and Sta-te of Ohio, have invented a new `and useful Heat-V ingFurnace, of which the following is a. specification; this applicationbeing an im' provement 'over my former application filed August 25,1919, Serial No. 319,7 94.

The invention relates to improvements in heating furnaces such as pairand sheet furnaces for sheet and tin mills, especially adapted for theuse o-f powdered coal and designed to prevent a stalactio formation ofsilicious or other solid products of combustion upon the roof of theheating chamber of the furnace.

'A very serious objection to furnaces'. of this type is that thesilicious' or other solid parts of the products of combustion in afinely divided state Vare carried along the roof o-f the heatingchamber, producing a stalactic formation thereon. this stalacticformation continuously drop upon the sheets o-r barswithin the heatingchamber, forming silicious spots or streaks thereon, which in subsequentoperations are not removed by the sulphuric acid bath.,

consequently these spots or streaks will nottake a coating of tin,thereby producing an .abnormal percentageof Wasters, thus entailing agreat loss in the cost of manufacture of tin sheets.

The primary object of the invention is to provide means fo-r preventingthe finely divided, silic-ious or'other solid parts of the products ofcombustion from traveling directly along the roof of the heatingchainber, thus preventing the accumulation of particles of siliciouslmatter iii a stalactic formation upon the roof of the heating'gchamber. y

These objects are attained b-y providing an inverted or depending bafliewall at the entrance to the heating chamber, preferably 'j ust beyondt'he usual bridge wall separating the heat-ing chamber from thecombustion chamber, and extending below the upper edge of said bridgewall, the silicious and other solid parts of the products ofVcoinbustion in a finely divided state, being deflected away from theroof of the heating chamber, preventing the stalactic formation thereonof the solid products of combustio-n.

Particles' of The vinvention thusV set forth in general4 terms isillustrated" in the accompanying.A

drawings forming part hereof, in which-l.-

Figure 1 is a plan view` ofa pairand. sheet furnace embodying theinvention; and' Fig. 2, a section on line 2 2, Fig.;1.l

VA practical'embodiinent of the invention is disclosed in theaccompanying drawings,

forming-,apart of this speciiioation-,=in whichr 'i similar numerals ofreference indica-te corred sponding parts throughout the several views.

A sheet furnace andvf-pair furnace are(k shown in the drawings, thisbeing the usual construction of furnace used'in"f tin plate or sheetmills, the bars vbeing heated in thev pair furnace and the sheets whichare rolled from these bars being reheated .in Y the sheet furnace. Itwill be understood, however, that this combination of the two.

furnaces formano-part of the invention and that annealing furnaces orany other heating furnaces may be constructed in accordance with therinvention.

Attention is: directed to Fig. v2 ofthe drawings, lwhich figure is alongitudinal section taken through the pair furnace. The

interior construction of the [sheet furnace is the same as lthe pairfurnace'withthe I exception that the sheetk furnace is necessarily madewider to accommodate the sheets. 1 n

The combustion chamber indicatedr generally by the numeral 1 isconsiderably larger than fis usual ini the forms of furnace at presentin general use and the pipe 2 which admits the powdered coalto thecombustion chamber is located near the bottom,

of the Vcombustion chamber, tlhle nozzle 3- of said pipe beinglpreferably directed up-rv wardly at substantiallyan angle vofA 45.

The pipe 2 enters the combustion chamber through a comparatively largeaperture-4 and extends through the lower portion of f Y the saidaperture. A dampera is-a-rranged to cover the aperture 4 and isconnectedv by means of a. -suitable cable or chain 6 with arcounterweiglit 7 which is preferably located at the front or working endof the yfurnace in position 'to be operated by the workmen who place thebars or sheets Within the furnace and remove` them therefrom.

The cable or chain 6 passes over suitable pulleys 8 mounted upon theupper po-rtion of the furnace. A bridge wall 9 is provided tendinghorizontally along the forward por-V tion'of the furnace as shown at 1land then upwardly as shown at 14 over the top of the furnace, the fluesfrom both furnaces Vextending Yacross the top of the furnace as shown at15 to a common stack ld A cleanoutdoor 17 is provided in the lowerportion of each of the flues and a clean-out door 18 is provided in eachof the combustion chambers for the purpose of removing the solidproducts of combustion.

' A depending baffle-wall 2O is 'provided at the 'entrance to theyheating chainb-erjust beyond the bridge wall 9 and preferablyextends'down a distance VVbelow the upper edge of' said bridge wall.coal enters the combustion chamber through the usual feed pipe`2, aslight air pressure being provided in the pipe for expelling the coalfrom the nozzle 3 in the usual manner. The' damper 5 is arranged toallow a. natural draft of air to enter the combustion chamber throughthe aperture ll, to produce the Vdesired kind of flame required for thework.

A bridge wall 22 is provided upon the hearth of the heating chamber at apoint just forward ofthe depending baille wall 20, as shown in Fig, 2`for the purpose of divertingfthe flame away from the rear ends of thebars or packs of sheets in the heating chamber indicated at B.

It has been found vthat without the use off this bridge wall, the flameisdiverted down- Y wardly by the baflie wall 20, against the rear endsof the bars or packs, heating this portion thereof to an extremelyhightemperature7 causing oxidization which is fatal in the production of tinsheets.

rlhe flame 'carrying the finely divide-d solid parts of the products ofcombustion of the coa-l, will be formed a short distance from the Vmouthof the nozzle' and will extend over the bridge wall 9 and against thebaffle wall 2O and then through thefheat-V ing chamber l() to the flues1l, in acurved path, as indicated'by the dot and dash line A shown inFig. 2, curving upwardly from the bafliewall 2 0 and then downwardly tothe flues 1l, withont contacting with the roof of the heating chamber.

fith the construction illustrated including the baffle wall 20, thesolid products of combustion are so deflected that they do not contactwith the roof of the heating cha-mber, the only stalactic formationproduced in this furnace being against the Ibaffle wall 20 toward thecombustion chamber and above the bridge wall 9 where the flame contactswith the roof of the combustion chamber.

rlhe powdered Any particles o-f this stalactic formation which drop uponthe hearth of the furnace will not damage the sheets or bars, as theywill be deposited upon the hearth at a point beyond thepoint which thesheets or bars occupy in the furnace. This formation may be easilyremoved through the clean-out door or streaks cau-sed by the dropping ofparticles of ythe stalactie formation of vproducts of combustion. Whentinned, there will be a much smaller percentage of .wasters among thesheets, as the solid portioiisof the products ofcombustion are notcarried: along the roof ofthe heating chamber there' by preventing the'stalactic formation of si-v licious or other solid products ofvcombustion thereon, precluding the dropping of particles thereofuponthe surface ofthe sheets. lt is well understood'that a 'metal-` liccoating will-'not adhere to or coverthe spots or streaks upon the sheetsformed by these particles of silicious or other solid product-s ofcombustion. l claim l. A heating furnace including a heating chamber, acombustion chamber communieating therewith and extending'downwardly toa. point beneath the level of the bottom'of the heating chamber andprovided in its lower portion with an aperture for admitting'atmosphericaiiga bridge wall between the heating chamber and combustion chamberabaille wall ldepending from thereof of the furnace beyond theA bridgewall and extending to a point below the level of the top 'of `thebridge'wall and a powdered fuel'Y pipe extending through the lowerportion of the aperture and directed toward the top of the bridge wall.

2.` A heating furnace including a heatingv chamber, a combustionchamber7 the upper portion of said'chainbers being connected by arestricted passage, al baffle wall dependingfroin the roof of the'heating chamber just beyond said restricted passage, and a powderedvfuel pipe extending into the lower portion Y of thecoinbustion chamberanddi- Y rected toward said restricted passage. c

3. A heating furnace including a heating chamber a combustion chamberthe u er portions of' said chambers being connected by a restrictedpassage, a baille wall depending vfrom the roof of the heating chambervjust forward of said restricted passage, a bridge wall upon the hearthof the heating chamber justv forward of said depending baffle wall, anda powdered fuel pipe extendig into the lower portion ofthe combustionchamber and direct-ed toward said restricted passage. 4 Y

ARTHUR J. lllAuiSKRliY.v

